gallus gallus pituitary: Topics by WorldWideScience.org

Sensitivity of embryos of chicken, domestic duck, and common eider duck to polychlorinated and non-halogenated aromatic hydrocarbons

This article will present the argument that the chicken embryo is especially appropriate as an animal model for studying the mechanism of the developmental toxicological effects of the polyhalogenated aromatic hydrocarbons (PHAHs). The PHAHs are a group of toxicologically related compounds including, in part, the polychlorinated dibenzodioxins, dibenzofurans and biphenyls. The chicken (Gallus gallus) embryo is relatively sensitive to the toxicological effects of the PHAHs being approximately two orders of magnitude more sensitive than the mature bird. The chicken embryo has been used to demonstrate general toxicological teratogeneicity, hepatotoxicity and neurotoxicity. Many of these effects, or analogous effects, have also been observed in mammals and fish. Thus, most animals appear to respond to the PHAHs with a similar toxicological profile, indicating that many of the biomarkers used for the PHAHs are valid across a number of species, ...

1996-12-31

Single photon emission tomography of the pituitary: preliminary communication.

Embryos of chicken (Gallus domesticus), domestic duck (Anas platyrhynchos), and common eider duck (Somateria mollissima) were exposed in ovo to PCBs and to polycyclic aromatic hydrocarbons. Two coplanar PCBs, 3,3{prime},4,4{prime}-tetrachlorobiphenyl (PCB {number_sign}77) and 3,3{prime},4,4{prime},5-pentachlorobiphenyl (PCB {number_sign}126), were considerably more lethal and potent as inducers of 7-ethoxyresorufin O-deethylase (EROD) in chicken embryos (Gallus domesticus) than in embryos of the other two species. In chicken embryos, these compounds caused edema and eye and beak deformities. An artificial mixture of 18 PAHs which all have been detected in environmental samples, was slightly more toxic to embryos of the domestic duck and the common eider duck than to chicken embryos. The most potent compound in the mixture was benzo(k)fluoranthene. When chicken embryo livers were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in vitro, ...

1995-12-31

Minimally Invasive Endoscopic Pituitary Surgery

A specific application of single photon emission tomography to the relative quantitation of the pituitary region is described together with the results obtained in 19 patients with pituitary adenoma...Full Text Available

1981-09-01

Medline Plus

... There has been a role for placement of yttrium or radioactive phosphorous in a tumor called craniopharyngioma, ...

Weaning and the Developmental Changes in Follicle-Stimulating Hormone, Pituitary Adenylate Cyclase-Activating Polypeptide, and Inhibin B in the Male Rat1

Transcranial management of pituitary tumours with suprasellar extension.

Pituitary Fshb concentrations increase markedly and selectively beginning on Postnatal Day 20 in the male rat. To evaluate the factors potentially responsible for this rise...Full Text Available

2008-04-01

Preparation of internally labelled rat pituitary somatotropin (growth hormone).

A consecutive series of 101 pituitary tumours treated in the 10 year period 1968-78 has been examined, giant lesions being excluded. There were 48 female cases and 53 male, women predominating in the...Full Text Available

1979-02-01

Isolation and structure of an untriakontapeptide with opiate activity from camel pituitary glands.

Rat somatotropin (growth hormone) was labelled biosynthetically by incubating anterior pituitary lobes with radioactive amino acids for 24 h in a simple buffered salts medium containing glucose. The...Full Text Available

1978-03-01

Hypothalamo-pituitary hormone insufficiency associated with cleft lip and palate.

The isolation of an untriakontapeptide from camel pituitary extracts has been described. Its structure has been determined and shown to be identical to the sequence of carboxyl-terminal 31 amino acids...Full Text Available

1976-04-01

Variations of endonasal anatomy: relevance for the endoscopic endonasal transsphenoidal approach

Two male patients with congenital cleft lip and palate first seen at ages 10.2 and 21.5 years presented with typical signs of hypothalamic-interior pituitary hormone deficiencies. They were found to...Full Text Available

1978-12-01

Variation in response to dexamethasone of a patient with Cushing's syndrome.

BackgroundThe endoscopic endonasal transsphenoidal approach (EETA) to the pituitary is performed by ear, nose, and throat (ENT) surgeons in collaboration with neurosurgeons but also...Full Text Available

2010-06-01

Response to CRH Infusion in Cocaine-Dependent Individuals

A patient with Cushing's syndrome due to a nonresectable chromophobe adenoma underwent external irradiation of the hypothalamic-pituitary area. The signs of Cushing's syndrome ameliorated subsequently...Full Text Available

1976-11-06

Pituitary gland height evaluated by MR in patients with {beta}-thalassemia major: a marker of pituitary gland function

ContextCorticotropin-releasing hormone (CRH), through the hypothalamic pituitary adrenal (HPA) axis and other brain stress systems, is involved in the emotional dysregulation...Full Text Available

2009-04-01

Menstrual Cycle: Basic Biology

In transfusion-dependent {beta}-thalassemia major, increased iron deposition in the pituitary gland has a cytotoxic effect leading mainly to hypogonadotropic hypogonadism. Our purpose was to assess in these patients the height of the pituitary gland and to evaluate whether it represents a marker of pituitary gland function. In 29 patients with {beta}-thalassemia major and 35 age- and gender-matched controls the pituitary gland height was evaluated in a midline sagittal scan using a spin echo T1-weighted (500/20 TR/TE) sequence. In all patients, an extensive endocrine evaluation was performed, including measurements of spontaneous and stimulated levels of gonadotropins, thyroid hormones, growth hormone, insulin-like growth factor, and adrenal hormones. The pituitary gland height was lower in thalassemic patients with hypogonadotropic hypogonadism (n=15) (mean 3.48; SD 0.46) than in ...

2001-12-01

Fractionated stereotactic radiotherapy in the treatment of pituitary macroadenomas

The basic biology of the menstrual cycle is a complex, coordinated sequence of events involving the hypothalamus, anterior pituitary, ovary, and endometrium. The menstrual cycle with all its...Full Text Available

2008-01-01

Age and the Thyrotropin Response to Hypothyroxinemia

BackgroundThe use of fractionated stereotactic radiotherapy (fsrt) has evolved with technical advances in noninvasive immobilization, radiation delivery, and image guidance....Full Text Available

2008-12-01

Effect of polychlorinated biphenyls (Aroclor 1254) on rhythmic pituitary-adrenal function. [Rats

Context: Some studies suggest altered pituitary functioning and TSH production with aging.Objective: Our objective was to test the hypothesis that less TSH production...Full Text Available

2010-08-01

Pituitary disease in childhood: utility of magnetic resonance; Patologia hipofisaria en la edad pediatrica: unidad de la resonance magnetica

Numerous studies have documented the general toxicity of the polychlorinated biphenyls (PCBs) and a sizeable literature has accumulated concerning the toxic effects of PCBs on a variety of homeostatic systems. However, current information regarding the effects of PCBs on rhythmic endocrine function is quite limited. Thus, the present study was undertaken to determine whether circadian periodicity in pituitary-adrenal function is affected by exposure to PCBs.

1983-09-01

Radiotherapy for nonfunctioning pituitary adenomas: from conventional to modern stereotactic radiation techniques

To assess the utility of magnetic resonance (MR) imaging in the study of pediatric patients with clinical suspicion of pituitary disease. We studied 18 patients aged 7 to 18 years.Fifteen had hormonal disturbances, two presented amenorrhea and 1 complained of headache, fever and symptoms of polyuria and polydipsia. All the patients were examined using a Siemens SP 42 1-Tesla MRI scanner. Sagittal and coronal T1-weighted spin-echo images were obtained; in addition T2-weighted spin-echo or fast spin-echo imaging was performed in ten cases and intravenous gadolinium was administered in nine. We found 9 patients with hypothalamic-pituitary dysgenesis, 2 with germinoma, 2 cases of pituitary hemosiderosis in patients with thalassemia, 2 cases of microadenoma, one abscess, one case of idiopathic central diabetes insipidus and one of Langerhans cell histiocytosis. MR enabled us to assess pituitary structural ...

2000-07-01

British Library Electronic Table of Contents (United Kingdom)

The initial management of nonfunctioning pituitary macroadenomas (NFAs) is usually surgery; however, a significant proportion of NFAs may require further treatment. Radiotherapy is currently used in patients with residual tumour and achieves excellent long-term control, but there are concerns about potential late toxicity. Stereotactic radiotherapy, both in the form of radiosurgery or fractionated stereotactic radiotherapy, has been developed as a more accurate technique of irradiation with more precise tumour localization and consequently a reduction in the volume of normal tissue, particularly the brain, irradiated to high radiation doses. A review of the literature suggests that new radiation techniques offer safe and effective treatment for recurrent or residual pituitary adenomas; how...

2007-01-01

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Radiolabelled D_2 agonists as prolactinoma imaging agents: Progress report for period February 1, 1988--January 31, 1989

Radiolabelled D/sub 2/ agonists as prolactinoma imaging agents: Progress report for period February 1, 1988--January 31, 1989

Targeted studies completed include the evaluation of tritiated N-0437, evaluation of "3"5S-cysteamine, evaluation of "1"8F-FDG and initiation of synthetic efforts towards the synthesis of iodinated N-0437 and pergolide analogs. The direction of the project has been changed due to several factors which include the decided lack of favorable experimental results, the excellence of results using muscarinic receptor ligands in pituitary, brain and heart and the contention of the DOE review panel that the original grant proposal was based on flawed assumptions together with their perceived lack of importance to pituitary imaging. In the final year of this grant, three studies will be completed. The first study is the continuation of synthetic efforts to prepare iodinated N-0437 and pergolide analogs for possible use as brain imaging agents. The second study is directed towards completion of biochemical evaluation of various muscarinic receptor ...

Pituitary function following megavoltage therapy for Cushings' disease; long term follow up

Targeted studies completed include the evaluation of tritiated N-0437, evaluation of /sup 35/S-cysteamine, evaluation of /sup 18/F-FDG and initiation of synthetic efforts towards the synthesis of iodinated N-0437 and pergolide analogs. The direction of the project has been changed due to several factors which include the decided lack of favorable experimental results, the excellence of results using muscarinic receptor ligands in pituitary, brain and heart and the contention of the DOE review panel that the original grant proposal was based on flawed assumptions together with their perceived lack of importance to pituitary imaging. In the final year of this grant, three studies will be completed. The first study is the continuation of synthetic efforts to prepare iodinated N-0437 and pergolide analogs for possible use as brain imaging agents. The second study is directed towards completion of biochemical evaluation of various muscarinic ...

1988-10-15

Pituitary function following megavoltage therapy for Cushings' disease; long term follow up

Eight patients who had received megavoltage therapy for Cushings' disease 5-12 years previously have been reviewed. The long term response to this therapy was assessed with respect to efficacy of treatment in inducing continued remission and disturbance of hypothalamic-pituitary function. One patient showed clear evidence of relapse of Cushings' disease. One patient had unequivocal hypopituitarism. Basal levels of growth hormone (GH), TSH, LH, and FSH were not statistically different from controls, but provocative testing revealed significant abnormalities of response of cortisol/ACTH, GH, prolactin and LH. Six out of eight patients had absent diurnal cortisol variation and five patients had elevated serum prolactin levels. Thus, in this group of patients normal pituitary-adrenal function has not been satisfactorily restored. It is clear that significant disturbances of hypothalamic-pituitary function follow megavoltage ...

1985-01-01

Neurocysticercosis Involving the Pituitary Stalk : Case Report and Literature Review

1985-02-01

Developmental Changes in Pituitary Adenylate Cyclase Activating Polypeptide Expression during the Perinatal Period: Possible Role in Fetal Gonadotroph Regulation

Neurocysticercosis (NCC) is the most common parasitic infestation of the central nervous system. Most cases of NCC are to related and/or associated with inflammation within the cerebral parenchyma....Full Text Available

2010-07-01

DIFFERENTIAL EXPRESSION OF HPA AXIS HOMOLOG IN THE SKIN

Normal reproductive functioning may require secretion of LH independently of FSH. Variation in GnRH pulse frequency and inhibin negative feedback are mechanisms for differential gonadotropin regulation;...Full Text Available

2009-10-01

Radiolabelled D2 agonists as prolactinoma imaging agents

SummaryHuman skin expresses elements of the hypothalamo-pituitary-adrenal (HPA) axis including pro-opiomelanocortin (POMC), corticotropin releasing hormone (CRH), the CRH receptor-1...Full Text Available

2007-02-01

[Functional state of the hypothalamo-hypophyseal-gonadal system in patients with chronic alcoholic intoxication].

During the past year, further studies on mAChR were conducted. These studies included verification of the difference in pituitary distribution based on ligand charge. The pituitary localization of TRB. A neutral mAChR ligand, was verified. The lack of QNB blockade of TRB uptake was tested by blockage with scopolamine, another mAChR antagonist and by testing the effect in a different strain of rat. Neither scopolamine or change of rat strain had any effect. We concluded that TRB uptake in pituitary is not a receptor-mediated process. Further studies were conducted with an additional quaternized mAChR ligand: MQNB. Pituitary localization of MQNB, like MTRB, could be blocked by pretreatment with QNB. We have tentatively concluded that permanent charge on a mAChR antagonist changes the mechanism of uptake in the pituitary. Time course studies and the effects of DES on myocardial uptake ...

1989-08-01

Human type I pituitary adenylate cyclase activating polypeptide receptor (ADCYAP1R): Localization to chromosome band 7p14 and integration into the cytogenetic, physical, and genetic map of chromosome 7

The function of the hypothalamo-pituitary-gonadal system has been studied in 118 males with different stages of alcoholism. Comparison with the control group has shown decreased levels of interstitial cell stimulating hormone (ICSH), follicle-stimulating hormone (FSH), and testosterone, and elevated concentrations of prolactin (Prl). Differences in the parameters of hormonal activity expressed in a varying degree of a decrease in FSH, ICSH, and testosterone, and a Prl elevation are related to change in mutual regulatory influences between the gonads and hypothalamo-pituitary complex. The most informative parameters were concentrations of Prl and testosterone (considering elevation in the former and reduction in the latter hormone) and the ratio of their concentrations. Difference of these parameters in each group (corresponding to the stages of alcoholism) may be used as an additional diagnostic criterion of chronic alcohol intoxication. ...

1987-01-01

Effect of aspirin on hypothalamic?pituitary?adrenal function and on neuropsychological performance in healthy adults: a pilot study

The gene encoding the human type I pituitary adenylate cyclase activating polypeptide receptor (ADCYAP1R1) was mapped to chromosome 7 by PCR analysis of genomic DNA from a human/rodent somatic cell hybrid mapping panel. This assignment was confirmed and the gene localized to chromosome band 7p14 by fluorescence in situ hybridization. A yeast artificial chromosome containing ADCYAP1R1 was identified in the CEPH {open_quotes}B{close_quotes} Mega-YAC library. This YAC includes two highly polymorphic dinucleotide repeat sequences that will facilitate genetic studies of the contribution of ADCYAP1R1 in disease states of the central nervous and neuroendocrine systems. 13 refs., 1 fig.

1994-10-01

British Library Electronic Table of Contents (United Kingdom)

Rationale Hypothalamic?pituitary?adrenal axis dysregulation predicts poor clinical and biochemical response to antidepressants. Antiglucocorticoids have therapeutic benefits but most have a troublesome adverse event profile. Aspects of neuropsychological performance, notably working memory, are susceptible to corticosteroid modulation and are impaired in depression. Aspirin has been shown to attenuate the adrenocorticotropic hormone (ACTH) and cortisol response to physiological challenge suggesting its potential to act as an augmenting agent in depression. Objectives To examine the effect of sub-acute (300?mg daily for 7?days) aspirin pre-treatment on the cortisol awakening response and the effect of acute (600?mg) and sub-acute aspirin on the neuroendocrine and neuropsychological response...

2009-01-01

Cloning of the cDNA and gene for a human D sub 2 dopamine receptor

Chronic maternal stress affects growth, behaviour and hypothalamo?pituitary?adrenal function in juvenile offspring

A clone encoding a human D{sub 2} dopamine receptor was isolated from a pituitary cDNA library and sequenced. The deduced protein sequence is 96% identical with that of the cloned rat receptor with one major difference: the human receptor contains an additional 29 amino acids in its putative third cytoplasmic loop. Southern blotting demonstrated the presence of only one human D{sub 2} receptor gene. Two overlapping phage containing the gene were isolated and characterized. DNA sequence analysis of these clones showed that the coding sequence is interrupted by six introns and that the additional amino acids present in the human pituitary receptor are encoded by a single exon of 87 base pairs. The involvement of this sequence in alternative splicing and its biological significance are discussed.

1989-12-01

British Library Electronic Table of Contents (United Kingdom)

Maternal stress during pregnancy, particularly that combined with low socioeconomic status (SES), has been linked to an increased risk for impaired behavioural and emotional development and affective disorders in children. In animal models, acute periods of prenatal stress have profound effects on hypothalamo-pituitary-adrenal (HPA) function and behaviour. However, few studies have determined the impact of chronic exposure to stress in animal models. The objective of this study was to determine the effects of chronic maternal stress (CMS) during the 2nd half of pregnancy and nursing on growth, locomotor behaviour and HPA axis function in juvenile guinea pig offspring. Pregnant guinea pigs were exposed to a random combination of variable stressors every other day over the 2nd half of gestat...

2008-01-01

Human Scalp Hair Follicles Are Both a Target and a Source of Prolactin, which Serves as an Autocrine and/or Paracrine Promoter of Apoptosis-Driven Hair Follicle Regression

Selective metabolic stimulation of the subfornical organ and pituitary neural lobe by peripheral angiotensin II

The prototypic pituitary hormone prolactin (PRL) exerts a wide variety of bioregulatory effects in mammals and is also found in extrapituitary sites, including murine skin. Here, we show by reverse...Full Text Available

2006-03-01

Ionizing radiation alters beta-endorphin-like immunoreactivity in brain but not blood

The subfornical organ is a major receptor area for one of the principal stimuli of thirst, the octapeptide, angiotensin II. In conscious water-sated rats, the authors examined the effects of intravenous infusion of angiotensin II on the rate of glucose utilization in the subfornical organ and in structures anatomically and functionally connected with it. Angiotensin II produced pressor and drinking responses and increased glucose utilization selectively in the subfornical organ and pituitary neural lobe and in no other brain structure. Treatment with the angiotensin II antagonist, sar1-leu8-angiotensin II, before intravenous administration of angiotensin II prevented metabolic stimulation of the subfornical organ and neural lobe. Captopril, an inhibitor of angiotensin-converting enzyme, reduced subfornical organ glucose metabolism to a level similar to that found in control animals. These results demonstrate that peripheral angiotensin II stimulates glucose ...

1985-01-01

Cocaine in pregnancy: the effect of maternal administration of cocaine on the maternal and fetal pituitary-adrenal axes.

Previous behavioral and pharmacological studies have implicated endorphins in radiation-induced locomotor hyperactivity of the C57BL/6J mouse. However, the endogenous opiate(s) responsible for this behavioral change have not been identified. The present study measured beta-endorphin-like immunoreactivity (beta-END-LI) in brain, blood, and combined brain and pituitary samples from irradiated and sham-irradiated C57BL/6J mice. After radiation exposure, levels of beta-END-LI decreased significantly in the brain. A similar, but not statistically significant, decline was measured in combined brain and pituitary samples. Concentrations of blood beta-END-LI were not changed by irradiation. These radiogenic changes in beta-END-LI are in some ways similar to those observed after other stresses. However, radiation-induced locomotor hyperactivity may be mediated more by alterations of beta-END-LI in the brain than in the periphery. Other endogenous opiate ...

1983-12-01

Trends in Neuroendocrinology

The effects of cocaine on the maternal and fetal pituitary-adrenal axis in vivo during pregnancy have not been reported. Six pregnant ewes and their fetuses underwent instrumentation at 113 to 119 days' gestation. Ewes were assigned to receive an intravenous bolus injection of vehicle or cocaine (0.5, 1.0, or 2.0 mg.kg-1) at 124 to 136 days' gestation. Maternal arterial blood gases, fetal pH and fetal PCO2 were unchanged after injection of cocaine or vehicle. After administration of 2.0 mg.kg-1 cocaine, arterial fetal PO2 fell 3.2 +/- 1.72 mm Hg (p less than 0.05) at +5 minutes, returning to baseline by +15 minutes. Maternal and fetal adrenocorticotropin levels rose within 5 minutes after the highest cocaine dose (p less than 0.05). There was a significant (p less than 0.05) increase in maternal cortisol at all doses of cocaine and in fetal cortisol at +15 minutes after the 2.0 mg.kg-1. PMID:1847006

1991-02-01

British Library Electronic Table of Contents (United Kingdom)

The mammalian circadian timing system is organized into hierarchical structures with a central clock in the suprachiasmatic nucleus (SCN) and subsidiary peripheral oscillators. After the discovery of the local clockwork in peripheral organs and tissues, which have a molecular makeup similar to the central pacemaker SCN, uncovering the roles of the peripheral clock in the rhythmic physiology has been an emerging goal in chronobiology. Glucocorticoid (GC) is a multifunctional adrenal steroid hormone that shows a robust circadian rhythm. The daily GC rhythm has long been thought to be governed by the SCN via the hypothalamus-pituitary-adrenal neuroendocrine axis. Recent findings, however, indicate that multiple regulatory mechanisms, including the adrenal intrinsic mechanism by the peripheral...

2011-01-01

Oligodendroglioma occurring after radiation therapy for pituitary adenoma

Mechanisms of obesity-induced male infertility

A 38 year old male dentist developed an oligodendroglioma of the left medial temporal lobe and parasellar region 12 years after radiotherapy with 6600 rads for acromegaly. The 30 cases of radiation-induced gliomas reported in the English literature are reviewed and analysed. The criteria for defining radiation-induced tumours of the central nervous system are proposed as follows: the tumour has a long quiescent ''latency period'', a location in the previously irradiated field, a verified histological difference from a primary condition, and does not arise from a primary condition associated with a genetic syndrome such as neurofibromatosis or tuberous sclerosis. The reported case fulfilled these criteria but appears to be the only reported radiation-induced oligodendroglioma.

1987-12-01

British Library Electronic Table of Contents (United Kingdom)

Male infertility, characterized by hypogonadism, decreased semen quality or ejaculatory dysfunction, accounts for approximately 20% of infertility cases. Obesity and metabolic dysfunction have been identified, among other causal factors, to contribute to male infertility. In the context of the Western world's `obesity epidemic', this article discusses three main biological mechanisms linking obesity to impaired male reproductive function: hypogonadism, testicular heat stress/hypoxia-induced apoptosis and endocrine disruption by `obesogens'. Among these, obesity-induced hypogonadism is undoubtedly the most clinically significant and is easily assessed. Rapidly expanding areas of research in this area include leptin modulation of kisspeptins and hypothalamic-pituitary-testicular hormone path...

2010-01-01

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Homologous radioimmunoassay for human prolactin

Exploration of the hypothalamic?pituitary?adrenal function as a tool to evaluate animal welfare

Although thee are descriptions of a range of radioimmunoassays for human prolactin in various biological fluids, only one of these is an homologous assay using human prolactin as the reference standard and tracer as well and an anti-human prolactin antiserum (Sinha, Y.N., Selby, F.W.; Lewis, U.; and Vanderlaan, W.P., 1973, J. Clin. Endocr., Vol. 36, 509). A homologous radioimmunoassay using human putuitary prolactin has been developed. The separation method is based on the double antibody solid phase system. Cross reactivity with human growth hormone (GH), placental lactogen (HPL), the pituitary protein hormones and prolactins of various species were studied as were values found in normal subjects in basal conditions and after a TRH injection. (author).

British Library Electronic Table of Contents (United Kingdom)

Measuring HPA axis activity is the standard approach to the study of stress and welfare in farm animals. Although the reference technique is the use of blood plasma to measure glucocorticoid hormones (cortisol or corticosterone), several alternative methods such as the measurement of corticosteroids in saliva, urine or faeces have been developed to overcome the stress induced by blood sampling itself. In chronic stress situations, as is frequently the case in studies about farm animal welfare, hormonal secretions are usually unchanged but dynamic testing allows the demonstration of functional changes at several levels of the system, including the sensitization of the adrenal cortex to ACTH and the resistance of the axis to feedback inhibition by corticosteroids (dexamethasone suppression t...

2007-01-01

Determinants of postoperative visual recovery in suprasellar meningiomas

British Library Electronic Table of Contents (United Kingdom)

Purpose Suprasellar meningiomas usually present with visual deterioration, including decreased visual acuity and/or visual field defects. Suprasellar meningiomas have a close relationship with the optic apparatus, arteries of the anterior circulation, pituitary stalk and hypothalamus, which makes safe surgical resection a challenge especially with dissection around an already compromised optic apparatus. In this report 21 patients operated on for a suprasellar meningioma over a 4-year period are reviewed. Postoperative outcome and visual recovery are evaluated, including analysis of its determinants. Methods Over a 4-year period (2002?2006), patients surgically treated for suprasellar meningiomas were included in this retrospective study. All tumors were located at the tuberculum sellae an...

2010-01-01

An animal model of social instability stress in adolescence and risk for drugs of abuse

British Library Electronic Table of Contents (United Kingdom)

There is increasing evidence that adolescence, like early life, is a sensitive period in which ongoing brain development can be influenced by environmental factors. This review describes our use of social instability as a model of mild adolescent social stress, its effects on social interactions and on hypothalamic?pituitary?adrenal function over the course of the procedure and in response to new stressors. The effects of social instability are sex-specific, with qualitative differences between the sexes on HPA function over the course of the stressor procedure, and with greater effects in males on behaviour observed during the social instability and greater effects in females on behavioural responses to drugs of abuse into adulthood, long after the stress exposure. The results from invest...

2010-01-01

Amphiphysin (Amph) maps to the proximal region of mouse chromosome 13

The neuroimmune-endocrine axis: pathophysiological implications for the central nervous system cytokines and hypothalamus-pituitary-adrenal hormone dynamics

Amphiphysin is a protein concentrated in neuronal synapses and peripherally associated with neurotransmitter vesicles. It is expressed in many neurons of the central and peripheral nervous systems, in the adrenal medulla, in the anterior and posterior pituitary, in cell lines of the endocrine pancreas, and in spermatocytes. Its subcellular localization and tissue distribution indicate a potential involvement in mechanisms of regulated exocytosis. A role in the dynamic organization of the membrane-associated cytoskeleton is suggested by structural homology to the products of two yeast genes, RVS161 and RVS167, whose mutation results in an abnormal actin distribution, disturbs budding morphology, and impairs cell entry into stationary phase. Limited stretches of sequence similarity, including an SH3 domain, are also shared with other actin-binding proteins. Amphiphysin is the dominant autoantigen in paraneoplastic Stiff-Man syndrome, a neurological autoimmune ...

1995-07-20

Scientific Electronic Library Online (English)

Abstract in english Cytokines are molecules that were initially discovered in the immune system as mediators of communication between various types of immune cells. However, it soon became evident that cytokines exert profound effects on key functions of the central nervous system, such as food intake, fever, neuroendocrine regulation, long-term potentiation, and behavior. In the 80's and 90's our group and others discovered that the genes encoding various cytokines and their receptors are e (more) xpressed in vascular, glial, and neuronal structures of the adult brain. Most cytokines act through cell surface receptors that have one transmembrane domain and which transduce a signal through the JAK/STAT pathway. Of particular physiological and pathophysiological relevance is the fact that cytokines are potent regulators of hypothalamic neuropeptidergic systems that maintain neuroendocrine homeostasis and which regulate the body's response to stress. The mechanisms by which cytokine ...

2000-10-01

Suppression of receptors for prolactin and estrogen in rat liver due to treatment with the growth hormone analogue produced by the tapeworm Spirometra mansonoides.

Salivary cortisol assessment in the evaluation of hypothalamic-pituitary-adrenal function

Somatogenic hormones play an important role in regulation of receptors for prolactin (PRL) and estrogen. Plerocercoids of the tapeworm, S. mansonoides produce a factor which mimics some, but not all of the actions reported for GH. Intact female rats were subjected to a constant infusion of plerocercoid growth factor (PGF) via a subcutaneous infection for two weeks to determine if PGF influences receptors for PRL, GH or estradiol. The rate of weight gain in the PGF-treated rats was accelerated in spite of a marked reduction in serum GH. Partially-purified PGF specifically displaced [125I]hGH from rat liver receptors but microsomes prepared from rats treated with PGF specifically bound significantly less [125I]hGH than microsomes from control rats. The reduction in [125I]hGH binding was not due to occupancy or to a change in affinity but to a suppression in receptor concentration. Scatchard analysis of [3H]estradiol binding in rat liver cytosols shows a 50% reduction in receptor ...

1986-01-01

Reversible downregulation of endocrine and germinative testicular function (hormonal castration) in the dog with the GnRH-Agonist Azagly-Nafarelin as a removable implant "Gonazon"; a preclinical trial

A simple, short and sensitive direct radio-immunoassay technique for the determination of salivary cortisol concentration was employed to assess saliva as a medium for evaluating cortisol response during endocrine testing in 9 controls and 40 patients. Results in controls suggested that an adequate salivary cortisol response to insulin hypoglycaemia was an increase of 150% above the basal value with a minimum peak of 15 nmol/l. Thirty-three patients were classified as being either good or poor responders to insulin hypoglycaemia on the basis of criteria for plasma cortisol levels. When the defined salivary cortisol response was used for assessment, all 33 patients were correctly categorized into the same response groups. The salivary cortisol response to intramuscular tetracosactin in 3 patients and an intravenous dexamethasone infusion in 4 patients confirmed the value of saliva as an assay medium. These studies show that the salivary cortisol response parallels that of total plasma ...

1984-05-01

British Library Electronic Table of Contents (United Kingdom)

Downregulation of anterior pituitary GnRH-receptors by application of a slow release GnRH-implant offers an effective and reversible alternative to surgical castration of the male dog. Aim of the present study was to test the efficacy and the underlying mechanisms of a new non-biodegradable controlled-release device implant (Gonazon, Intervet, containing 18.5mg of the GnRH-agonist Azagly-Nafarelin). Eight male beagle dogs were implanted s.c. at the para-umbilical region. In four dogs implant removal was after 180 days (group 1), in the other four dogs after 365 days (group 2). Eleven weeks after implantation availability of LH was reduced (p<0.0001) by 70%. After an initial increase lasting for about 4 days, testosterone (T) and estradiol (E2) concentrations decreased (p<0.0001) to basal l...

2009-01-01

Hypothalmic hypopituitarism following cranial irradiation for nasopharyngeal carcinoma

Screening for congenital hypothyroidism in Lebanon

Eight patients, one male and seven females, with no pre-existing hypothalamic-pituitary disease, who developed symptoms of hypopituitarism following cranial irradiation for nasopharyngeal carcinoma were studied 5 years or more after radiotherapy. All were GH deficient. Four of the patients with no GH response during insulin tolerance tests (ITT) showed increased GH in response to synthetic human growth hormone releasing factor (GRF-44). Four patients had impaired cortisol responses to ITT, and gradual but diminished cortisol responses to ovine corticotrophin releasing factor (CRF-41). There was no significant difference between mean peak increments in response to ITT and those in response to CRF-41. TSH responses to TRH were delayed in five and absent in two patients; four of these had low free T4 index. Prolactin was raised in all seven women and increased further in response to TRH. Two patients had impaired gonadotrophin responses to LHRH. None of the patients ...

1986-06-01

On the cells of origin of radiogenic thyroid cancer: New studies based on an old idea

Full text.National programs of neonatal screening were introduced in most countries and have proved their effectiveness against different types of retardation in children. Congenital hypothyroidism is one of the most common causes of physical and mental retardation in children. Programs of screening have shown that the incidence of this disorder is ethnic-background: it is low in Africans: 1-32000 whereas it is 1-3500 and 1-5000 in Hispanic and European newborns respectively. No previous mass screening programs were done in Lebanon. For this purpose, this program was introduced in collaboration with the IAEA. Cord blood is spotted into circles on filter paper just after delivery. These samples are air-dried at room temperature and kept at 4 degree C. They are then collected from hospitals to be screened. In the laboratory, all samples are assayed for IRMA TSH first. Those showing high or borderline TSH level (20mU/L) are then assayed for RIA TT4. Only those showing straight forward ...

1999-11-02

Molecular aspects involved in swimming exercise training reducing anhedonia in a rat model of depression.

We have presented evidence that the functional thyroid follicles (follicular units, FU) which are formed in grafts of monodispersed rat thyroid cells, and hence the thyroid tumors which later develop in such grafts, are clonal in origin. Recent studies have been designed to investigate: whether cell number-dependent inhibition of promotion-progression is mediated by remote hormonal feed-back, local cell-cell interactions, or both; the cell population kinetics of the clonogen subpopulation during goitrogenesis and goiter involution; and the effect of prolonged exposure to high levels of TSH (thyrotropin) on the capacity of the clonogens to give rise to functional FU. The results indicate that local cell-cell interactions play an important role in the cell number-dependent suppression of neoplastic promotion-progression. They also show that if sufficient thyroid cells are grafted, the thyroid-pituitary axis can be reestablished in thyroidectomized rats fed normal ...

1990-01-01

Localisation of the neuropeptide PACAP and its receptors in the rat parathyroid and thyroid glands.

Patients suffering from depression frequently display hyperactivity of the hypothalamic-pituitary-adrenal axis (HPA) resulting in elevated cortisol levels. One main symptom of this condition is anhedonia. There is evidence that exercise training can be used as a rehabilitative intervention in the treatment of depressive disorders. In this scenario, the aim of the present study was to assess the effect of an aerobic exercise training protocol on the depressive-like behavior, anhedonia, induced by repeated dexamethasone administration. The study was carried out on adult male Wistar rats randomly divided into four groups: the "control group" (C), "exercise group" (E), "dexamethasone group" (D) and the "dexamethasone plus exercise group" (DE). The exercise training consisted of swimming (1 h/d, 5 d/wk) for 3 weeks, with an overload of 5% of the rat body weight. Every day rats were injected with either dexamethasone (D/DE) or saline solution (C/E). Proper positive ...

2011-06-15

Inherited partial direct duplication of 11q: First report and possible association with a midline developmental field defect

PACAP (pituitary adenylate cyclase activating polypeptide) is widely distributed neuropeptide acting via three subtypes of receptors, PAC(1), VPAC(1) and VPAC(2). Here we examined the localisation and nature of PACAP-immunoreactive nerves in the rat thyroid and parathyroid glands and defined the distribution of PAC(1), VPAC(1) and VPAC(2) receptor mRNA's. In the parathyroid gland a large number of nerve fibres displaying PACAP-immunoreactivity were distributed beneath the capsule, around blood vessels and close to glandular cells. Most of the PACAP-nerves were sensory, since they co-stored CGRP (calcitonin-gene-related peptide) and were sensitive to capsaicin-treatment. mRNA's for PAC(1) and VPAC(2) receptors occurred in the parathyroid gland, mainly located in the glandular cells. In the thyroid gland PACAP-immunoreactive nerve fibres were associated with blood vessels, thyroid follicles and parafollicular C-cells. A high degree of co-existence between PACAP and ...

2010-12-19

Double-antibody solid-phase radioimmunoassay: a simplified phase-separation procedure applied to various ligands

A 36-year-old woman underwent amniocentesis for advanced maternal age. The fetal karyotype had an extra dark staining G band on the long arm of chromosome 11 with no other identifiable abnormalities. FISH studies using a chromosome 11 paint probe confirmed the origin of the extra band. The abnormality was identified as a partial duplication of 11q: 46,XX dir dup (11)(q13.5q21) or (q21q23.1). The specific duplicated band could not be identified with certainty. Detailed fetal sonograms were normal. Family studies revealed the identical duplication in the mother but normal karyotypes in both maternal grandparents. The mother had strabismus and a short tongue frenulum which required surgical correction. Menses occurred late in adolescence and complete development of secondary sexual characteristics was delayed until adulthood. An infertility evaluation revealed duplication of the uterus, cervix, and vagina. An evaluation for metorrhagia identified a pituitary adenoma ...

1994-09-01

Double-antibody solid-phase radioimmunoassay: a simplified phase-separation procedure applied to various ligands

The purpose was to develop a simplified and reliable method of separating free from antibody-bound ligand using a precipitating antibody linked to a cellulose derivative. Dose-response curves and control sera were set up in parallel for various pituitary and placental polypeptides, steroid hormones, insulin, glucagon, triiodothyronine, thyroxine, angiotensin I, calcitonin, gastrin, cyclic AMP, and digoxin. After first-antibody reactions had reached equilibrium, free and bound ligand were separated using a double-antibody solid-phase system in parallel with conventional methods, including dextran-coated charcoal, double-antibody precipitation, single-antibody solid phase, organic solvents, salt precipitation, and anion-exchange resins. The effect of variations in temperature, incubation time, protein content, pH, and amount of separating material added were studied. The results showed that separation was complete within 1 hr for small ligand molecules and within 2 ...

1980-06-01